Solid-state lighting apparatus and methods using energy storage with segment control

摘要

A lighting apparatus includes a rectifier circuit configured to be coupled to an AC source and to produce a rectified voltage from an AC voltage and a string including at least two serially-connected LED segments and coupled to the rectifier circuit. A segment control circuit is configured to selectively bypass at least one segment of the string responsive to the rectified voltage. An energy storage circuit is coupled to the rectifier circuit and controls current flow between at least one energy storage device and the string. A control circuit controls the segment control circuit and the energy storage circuit. The segment control circuit may support a current from the rectifier circuit through all of the segments in the string circuit at a peak of the rectified voltage and the energy storage circuit may charge the at least one energy storage device to a voltage near the peak of the rectified voltage.

主权项

1. A lighting apparatus comprising:
a string comprising at least two serially-connected light-emitting diode (LED) segments and configured to be coupled to a source of a varying voltage; a segment control circuit configured to selectively bypass at least one segment of the string responsive to the varying voltage; an energy storage circuit configured to charge at least one energy storage device from the source of varying voltage and to control current flow between the at least one energy storage device and the string; and a control circuit configured to cause the segment control circuit and the energy storage circuit to couple the at least one energy storage device in parallel with a first set of the at least two LED segments to charge the at least one charge storage device and to discharge the at least one charge storage device through a second set of the at least two LED segments.